Jack Daniel's Old No.7 Tennessee Sour Mash Whiskey (Liter)True to Mr. Jack's whiskey making tradition, every batch of Jack Daniels's whiskey is charcoal mellowed drop by drop, then aged in handcrafted barrels. The Tennessee Sippin Whiskey is ready only when the master tasters say it is. Using their senses, just like Jack Daniel's himself did. In fact, more than a century later, the Tennessee Whiskey is still judged the same way. By the way it looks. By the way it smells. And, of course, by the way it tastes.